package Package1;
//继承的格式：
//class 子类名 extends 父类名{}
public class SonStudent extends Student{
    public String email;
    String cardId;
    public int history;

    public void showhistory(){
        int history=999;

        System.out.println(history);
        System.out.println(this.history);
        System.out.println(super.history);

        super.history=666;
        System.out.println("==================");
        System.out.println(history);
        System.out.println(this.history);
        System.out.println(super.history);
    }
}
